wet cables

[jimbo123]

Is it practible to use sumps to wpump auto in underground vaults that fill with water ? I am sure there is water in the conduit before and after the vault too . Can this help in aiding and preventing the deterorating of the cable ?

 

[iwire]

Sump pumps are fairly common in underground vaults in my area.

 

[Dennis Alwon]

I am not sure that water is a problem with wire rated for wet location although there does seem to be a difference between marine wire and wet location. I have seen TW wire used in wells-- not sure that is done anymore as UF seems to be the ticket now.

I agree a sump pump is a good idea for the vault.

 

[jimbo123]

The reason i ask this question it doesn't seem right that energized wires are under water for who knows how long and does it cause problems

 

[Dennis Alwon]

The reason i ask this question it doesn't seem right that energized wires are under water for who knows how long and does it cause problems

energized wires are in water all the time. Power companies direct bury cables and wires rated with a "W" in the insulation type are suitable for wet location.

Is wet location suited for immersion in water???? I think so but am not certain.

 

[don_resqcapt19]

At the industrial plant I often work at they have 20,000+ feet of underground 5kV distribution in duct banks. Before they put sump pumps in the manholes, I was replacing about one cable section a year. About 15 years ago they put pumps in all of the manholes and I have only replaced one cable section since then. There may be other reasons, but I think a big part is not having the cables under water all the time.

 

[mbeatty]

At the industrial plant I often work at they have 20,000+ feet of underground 5kV distribution in duct banks. Before they put sump pumps in the manholes, I was replacing about one cable section a year. About 15 years ago they put pumps in all of the manholes and I have only replaced one cable section since then. There may be other reasons, but I think a big part is not having the cables under water all the time.

This makes sense to me. My experience has seen many more cable failures in immersed applications as opposed to just wet applications.

 

[Dennis Alwon]

I suspect the minerals in the soil that leech into the conduit may be bad for the insulation if the insulation is failing. As I stated before they do make marine wire for a reason.

I am surprised that the insulation, that Don talked about, failed so quickly.

 

[ptonsparky]

The biggest threat to the wires in water is when the water freezes.

 

[don_resqcapt19]

The biggest threat to the wires in water is when the water freezes.

I agree. I submitted a proposal to require underground conduits to installed below the frost line, but it did not get anywhere.